Rapidly rotating late B-type stars : spots or pulsations ?

Recent space based photometry (CoRoT & MOST) delivered a few
late B-type stars, where the variability shows intriguing similarity
with the light curves of cool, differentially rotating spotted stars. A
pilot study (Degroote et al., 2009) showed that it is possible to
explain both the light curve variability and the spectral line profiles
with a differentially rotating spot model. However, white light
photometry alone is not sufficient to disentangle variability due to
spots or pulsations. Much effort is devoted to building models that can
explain all of the observations simultaneously in one consistent model,
a method which we have generalised also to binary and multiple stars,
and other types of observations. After the pilot study, more targets
were looked for and found. The multicolour spaced based photometry and
ground based spectroscopy available for some of these targets allow for
a follow-up study to explain the observations and understand these objects.